In image sensors of the related art, there has been no frame-storable memory (DRAM (Dynamic Random Access Memory) etc.) or a memory capable of storing a sufficient amount of lines (SRAM (Static Random Access Memory) etc.). Therefore, various processing such as reading of pixel signals, analog processing, digital processing, and output processing, that are carried out in the image sensors, have been executed at the same processing speed and processing rate (frame rate).
Incidentally, as a method of reading out signals from pixels in a pixel array unit in the image sensor, there has been a technique of providing a nonvolatile memory subsequent to a signal processing unit that digitizes analog pixel signals read out from pixels and reading out the digitized signals at high speed using the nonvolatile memory (see, for example, Patent Document 1).
Patent Document 1: Japanese Patent Application Laid-open No. 2004-64410